CHICAGO — The entire night felt uncomfortable despite the Celtics leading
the Bulls from start to finish, a true rarity at the United Center.

The fourth quarter began with the Celtics holding a 13-point cushion but ended with them clinging to tenuous leads and needing to execute offensively to seal the victory. They were challenged extensively by the shorthanded Bulls but the visitors passed every test, including a critical Kevin Garnett dunk that helped clinch Monday night’s 101-95 victory.

Garnett struggled most of the evening but Doc Rivers called the same play twice — Garnett coming off a pick-and-roll with Rajon Rondo — and it resulted in easy dunks on consecutive plays in the final 2:35. The final dunk, with 41.9 seconds left, extended the lead to 4 as the Celtics gained their third road win in four games.

On Friday, the Celtics appeared in disarray, crushed after trailing nearly the entire way of a 106-100 loss to Philadelphia. Four days later, after road wins over teams expected to make the playoffs, the Celtics have gained confidence. Both times they built leads with clutch baskets and strong defense.

The Bulls converted one field goal in the final 3:33 and committed five turnovers in the final quarter, the last a 24-second violation with 1:28 left.

“It’s a couple of days in a row now, starting the second half of the Milwaukee game [Saturday], our team is starting to find their way,” Rivers said. “We thought coming in with this group that we could score. That it just takes time. I thought by far this was our best rhythm offensively.”

Since the second half against the Bucks, the Celtics are shooting 51.2 percent from the field with just 12 turnovers. They committed a season-low eight Monday, one of the reasons they raced to a 21-10 lead.

“We played pretty well offensively, besides the turnovers I had, other than that we took pretty good care of the ball,” said Rondo, who committed five turnovers. “We got out on the break, kept it simple offensively and except the stretch that we missed nine shots in a row [in the fourth quarter], we played pretty good.”

The Celtics expected this type of production from the outset of the season but developing a rhythm has been difficult. All five starters scored in double figures while the bench helped out with a 11-for-21 shooting performance.

They appeared ready to coast when Garnett drained a stepback jumper for an 87-74 lead with 10:08 left. The offense was flowing and the Bulls had no answer.

But Celtics nemesis Joakim Noah single-handedly sparked a Chicago run, scoring a conventional 3-point play and then a leaning jumper. Luol Deng followed suit with another 3-point play and then Noah scored a layup, all in the span of 1:22 to shrink the
hosts’ deficit to 87-84.

The Bulls had several chances to even the game, but the Celtics’ defense tightened, an encouraging sign since the offense missed 10 of the first 12 shots of the period. Jason Terry stopped Chicago’s rally with a long 2-pointer in front of Chicago’s bench followed by some trash talk.

The Bulls never relented. Deng and Noah followed with layups to slice the deficit to 91-88 with 3:35 left. After Garnett completed an alley-oop dunk for a 95-89 lead, the Bulls rallied yet again with two Marquis Teague free throws and a frustrating Deng layup. He missed two free throws and Taj Gibson chased down the offensive rebound and fed him streaking to the basket.

Without Derrick Rose, the Bulls were even scrappier, especially Deng, who again burned the Celtics with 26 points and 11 rebounds. But the play of Brandon Bass offset the production of the Chicago bigs. After dislocating his right ring finger in the first quarter, he returned and finished with 16 points, 5 rebounds, 3 assists, and 2 blocked shots.

His dunk with 22.9 seconds left extinguished Chicago.

“We’re a veteran ballclub and we thrive in situations where it’s a tight ballgame, we’ve been in that situation plenty of times,” said Terry, who scored 13 points. “We know what we have to do to close games out. On one end it’s getting stops defensively and offensively, make or miss, getting the shot that we want. We were able to do that.”

The Celtics controlled most of the first half following a 12-2 first quarter run that extended the lead to 21-10. The Bulls made spirited runs as Deng sparked an 8-4 run to begin the second quarter to reduce the deficit to 41-38. But the Celtics continued to counter every Chicago run, coming back with a 10-0 surge sparked by Bass’s 6 points.

After the Bulls made another surge, Bass canned another jumper and Terry drained a 3-pointer for a 58-46 lead. No lead was safe as the Celtics learned.

Boston entered Monday sixth in the NBA in field goal percentage but had been having trouble scoring points consistently because of a lack of cohesion and turnovers. That wasn’t an issue Monday night.

“Maybe this will be the start of something where we start playing more consistent,” said Paul Pierce, who finished with 10 points, 6 rebounds, and 5 assists. “I’m glad we got it together here on the road. We saw what we’re capable of when we move the ball and it carried over to [Monday’s] game.”